1. Field of the Invention
This invention relates to a cassette tape recorder suitable for reproducing a selected kind of information out of various kinds of recorded information.
2. Description of the Prior Art
Cassette tape recorders are now in wide use, for example in the form of stereophonic cassette decks, portable miniaturized cassette recorders and the like. Among these, portable type cassette recorders are often used to record meetings, conferences, lectures and the like. Further, the portable type cassette recorder can be used as "an audio memorandum " for recording various matters.
When the cassette recorder is used to make a record of a meeting, it is frequently desired to selectively reproduce the words of a specific speaker. On the other hand, when the recorder is used as an audio memorandum for recording various items such as schedules, expenses and the like, it would be convenient to be able to reproduce a selected item out of the recorded items.
Also, in the case of recording different musicians or different kinds of music, many users of tape recorders feel a desire to selectively reproduce the music of a specific musician or of a special kind.
There has been known a method of first recording tunes with spaces left between adjacent tunes and then, in reproducing, to count the number of spaces in order to locate the beginning of a desired tune. However, there has not been known a method of selectively reproducing tunes of desired kind out of randomly recorded tunes of various kinds.
There is disclosed in our U.S. Patent Application Ser. No. 384,808, a cassette tape recorder for selectively reproducing information of a desired kind out of randomly recorded information of various kinds.
The cassette tape recorder of this U.S. Patent application is provided with means for recording differently coded address signals on a magnetic recording tape and means for searching the tape for a designated address signal upon reproduction. Before recording a piece of information, an address signal selected in accordance with the kind of information to be recorded is first recorded on the recording tape and the piece of information is recorded following this address signal. When the code of an address signal is designated upon reproduction, the tape is fed at a relatively high search speed and when one of the address signals having the designated code is picked up, the tape feeding speed is reduced to the reproducing speed to reproduce the piece of information following the address signal. When reproduction of the information is completed and the next address signal is picked up, the tape feeding speed is again changed to the search speed to search for the next address signal having the designated code. All the pieces of information of the desired kind are thus selectively reproduced.
In the address signal recording type cassette tape recorder, generally the address signal is recorded using a recording magnetic head, and is picked up by a reproducing magnetic head. If the address signal and the audio signal of the information are recorded on a single recording track, there arises a problem that when an audio signal resembling the address signal is recorded, the searching means is apt to confuse the audio signal with the address signal. For example, there is a possibility of the audio signal being picked up as an address signal, whereby information not intended to be reproduced is accidentally reproduced, or the possibility of information to be reproduced not being reproduced. Further, if a component of the address signal is mixed with the audio signal, the quality of the reproduced sound is lowered.